Answer
Exodus 30:13 mentions a shekel of the sanctuary, stating, “Each person who crosses over to those already counted [in the census] is to give a half shekel, according to the sanctuary shekel, which weighs twenty gerahs. This half shekel is an offering to the LORD.”
Scholars are uncertain about the exact nature of a shekel, but here is one calculation of its value: the sanctuary shekel was defined as 20 gerahs. A gerah has traditionally been measured as 1/50 of an ounce, or 0.6 gram. The sanctuary shekel would then be equivalent to 0.4 of an ounce of gold (20 times 1/50 of an ounce), or 12 grams. Based on a price of 46.43 USD per gram, the approximate value of a sanctuary shekel would be $557.16 in today’s market.
An important distinction to note is that the standard shekel and the sanctuary shekel were two different weights. This is why the shekel in Exodus 30:13 is specified as a particular type of shekel known as “the shekel of the sanctuary.” This shekel was defined by the weights kept in the tabernacle as the standard.
A standard shekel weighed 11.5 grams. Later on, a “shekel” would also refer to a coin. In Amos 8:5, God condemns the use of a false shekel: “Making the ephah small and the shekel large, falsifying the scales by deceit” (NKJV).
Throughout the Old Testament, the shekel was used to measure gold «And it came to pass, as the camels had done drinking, that the man took a golden earring of half a shekel weight, and two bracelets for her hands of ten shekels weight of gold; », (Genesis 24:22), cinnamon «Take thou also unto thee principal spices, of pure myrrh five hundred shekels, and of sweet cinnamon half so much, even two hundred and fifty shekels, and of sweet calamus two hundred and fifty shekels, », (Exodus 30:23), hai
Regarding «And when he polled his head, (for it was at every year’s end that he polled it; because the hair was heavy on him, therefore he polled it;) he weighed the hair of his head at two hundred shekels after the king’s weight. », (2 Samuel 14:26), iron «And Hushai said unto Absalom, The counsel that Ahithophel hath given is not good at this time. », (2 Samuel 17:7), myrrh «Take thou also unto thee principal spices, of pure myrrh five hundred shekels, and of sweet cinnamon half so much, even two hundred and fifty shekels, and of sweet calamus two hundred and fifty shekels, », (Exodus 30:23), and food rations «And thy meat which thou shalt eat shall be by weight, twenty shekels a day: from time to time shalt thou eat it. », (Ezekiel 4:10).
Outside of the Books of Moses, only one passage mentions the sanctuary shekel. Ezekiel 45:12 says, “The shekel is to consist of twenty gerahs. Twenty shekels plus twenty-five shekels plus fifteen shekels equal one mina.” Though not mentioned explicitly as the sanctuary shekel, the same amount is referenced. Interestingly, this is the same section of Scripture in which Ezekiel prophesies regarding the future Jewish temple (often referred to as the Millennial Temple).
The sanctuary shekel differed from both the shekel and the common weight. Approximations can be made to give an idea of the value of a sanctuary shekel, but uncertainty remains regarding the exact weight. The important thing is that there was a standard system of weights and measures, and God’s people paid a tax during the census under Moses. This tax was used to provide for the needs of the tabernacle and its leaders.